The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
https://snyk.io/vuln/SNYK-UPSTREAM-PYTHONCPYTHON-1074933
https://github.com/python/cpython/pull/24297
https://snyk.io/blog/cache-poisoning-in-popular-open-source-packages/
http://www.openwall.com/lists/oss-security/2021/02/19/4
https://lists.debian.org/debian-lts-announce/2021/02/msg00030.html
https://lists.apache.org/thread.html/[email protected]%3Cdev.mina.apache.org%3E
https://security.netapp.com/advisory/ntap-20210326-0004/
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
https://lists.debian.org/debian-lts-announce/2021/04/msg00015.html
https://security.gentoo.org/glsa/202104-04
https://lists.apache.org/thread.html/[email protected]%3Cusers.airflow.apache.org%3E
http://www.openwall.com/lists/oss-security/2021/05/01/2
https://lists.apache.org/thread.html/[email protected]%3Cannounce.apache.org%3E
https://www.oracle.com/security-alerts/cpuApr2021.html
https://www.oracle.com//security-alerts/cpujul2021.html
Source: MITRE
Published: 2021-02-15
Updated: 2022-03-04
Type: CWE-444
Base Score: 4
Vector: AV:N/AC:H/Au:N/C:N/I:P/A:P
Impact Score: 4.9
Exploitability Score: 4.9
Severity: MEDIUM
Base Score: 5.9
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H
Impact Score: 4.2
Exploitability Score: 1.6
Severity: MEDIUM